Issue: A customer may report an audible sound (groan type noise) from under bonnet immediately after the vehicle is unlocked and the vehicle stationary. The sound will extinguish after several seconds and is generated by the Acoustic Vehicle Alert System (AVAS) sounder fitted to Plug-in Hybrid Electric vehicles (PHEV). The AVAS is located behind the grille at the front of the vehicle.
Cause: Software error in the Audio Amplifier Module (AAM) related to a communication timing error during wake up when vehicle is
